Please refer to FIG. 1 which illustrates a three-dimensional view of a socket structure in the prior arts, and FIGS. 2A˜2B which illustrate a front view and a back view of the socket structure in the prior arts. As shown in these figures a socket 1 includes a plastic main body 10 having an indentation 11 and two terminals 12 mounted in the indentation 11, wherein the two terminals 12 are employed to be connected with a corresponding plug (not shown), and furthermore, the two terminals 12 are respectively and directly contacted with a conducting piece 13, as shown in FIG. 2B.
Please refer to FIG. 3 which illustrates a structural view of a terminal of a conventional socket. As shown in FIG. 3, in the conventional socket, a terminal 12 includes a central pillar 121 having a first end 1211 and a second end 1212, and an outer ring 122. As to the inner structural of the conventional socket, please refer to FIG. 4 which shows the A–A′ sectional view of the socket shown in FIG. 2A. As shown in FIG. 4, the terminal 12 and the plastic main body 10 are assembled together through riveting the second end 1212 of the terminal 12.
The steps for assembling of the socket are as followed. Firstly, the two terminals 12 including the outer ring 122 are respectively assembled into the indentation 11 of the plastic main body 10, wherein the plastic main body 10 further includes two troughs in the indentation 11, and each of the two troughs has a shape identical to the shape of the outer ring 122 and the second end 1212 of the terminal 12. Then, when the two terminals 12 are respectively assembled into the troughs 11 of the plastic main body 10, the outer ring 122 of the terminal 12 will exactly reject against the plastic main body 10 and the second end 1212 of the terminal 12 will protrude out of the plastic main body 10. At this time, the conducting piece 13 is sleeved on the second end 1212 so as to contact the surface of the plastic main body, and then, the second end 1212 is riveted by an external force so as to fixedly reject the conducting piece 13 on the main body 10, as shown in FIG. 4. Simultaneously, the conducting piece 13 therefore forms a circular contact 40 with the terminal 12 for being a path for an electrical conduction.
However, it is obvious that the contact area of the circular contact 40 in the conventional socket structure is limited so that the electrical connection is therefore limited, too. Furthermore, in this conventional socket structural, because the terminal 12 is fixed through a cooperation of the outer ring 122, parts of the main body 41, the conducting piece 13 and the riveted second end 1212, when the socket is connected to a plug for power supply, parts of the plastic main body located between the outer ring 122 and the conducting piece 13 are always melted and deformed owing to the heat produced during electrical conduction, as shown by the label 50 in FIG. 5. Moreover, since the melted and deformed parts of the plastic main body can not be recovered when the temperature is lowered down, the above described originally stable and tight cooperation among all the elements will be destroyed so that the terminal might become movable, namely, the cooperation for fixing the terminal is “loosed”.
In addition, because the terminal 12 is loosed, the assembling and separation between the socket and the plug will become a difficult job and the contact between the terminal 12 and the conducting piece 13 will also become a loosed contact which can not always keep in contact so as to cause an unstable power supply. Particularly, in this conventional socket structure, the contact between the conducting piece 13 and the terminal 12 is only achieved by the circular contact 40 and the riveted second end 1212, and thus, it is easy to cause a shake of the conducting piece 13 as long as the plastic main body 10 is melted. Therefore, the contact therebetween will be further reduced thereby. Hence, it is obvious that for the user, this unstable socket structure is an inconvenience. Besides, if the socket is employed to connect with an electrical equipment which needs a stable voltage for perfect operation, in fact, this unstable electrical contact might further damage the electrical equipment.
Consequently, the conventional socket structure described above not only might own a loosed terminal as the time goes by but also cause an unstable power supply, and thus, it is urgent to be improved either in structure or in function.
Because of the technical defects described above, the applicant keeps on carving unflaggingly to develop a “socket structure and method for forming the same” through wholehearted experience and research.